There are four different species of echidna divided into two genera:
There's the long-beaked echidna, from the genus Zaglossus...
... and the short-beaked echidna from the genus Tachyglossus
Short-beaked echidnas thrive throughout Australia and parts of New Guinea...
... while long-beaked echidnas (which make up 3 of the 4 species) are found mostly throughout New Guinea.
One species of long-beaked echidna, Z. attenboroughi, is named after broadcaster and naturalist Sir David Attenborough.
Short-beaked echidnas are much smaller than their long-beaked cousins, but they have longer spines.
The echidna, along with the platypus, are monotremes, and are the only egg-laying mammals on the planet.
The pregnant female lays her egg into her pouch, which hatches after about 10 days revealing the young echidna.
Female echidnas do not have nipples, and instead feed their young by secreting milk from a special patch in their pouch.
The echidna's body is covered with two-inch long spines, which are modified hairs.
They have snouts used as both a mouth and nose.
Their mouths are tiny and toothless, and they eat by scooping up ants, termites and other insects with their long, sticky tongues.
As it doesn't have teeth, the echidna uses hard pads on the roof of its mouth to help break down food.
At 32°C (89°F), the echidna has the lowest body temperature of any mammal.
The average lifespan of the echidna is around 16 years in the wild, though in captivity they can live much longer (sometimes up to 50-years-old).
Echidnas are commonly found in woodlands and forests, where they hide under vegetation.
They're not big fans of extreme weather conditions, and will seek shelter in caves, rock crevasses or even the burrows of other animals.
Echidna's have big brains for a creature of their size, with the neocortex making up half of the echidna's total brain size.
Echidnas have electroreceptors at the ends of their snouts, which is primarily used for sensing and locating prey.
Their strong arms and sharp claws make them extremely powerful diggers.
Echidnas are incredibly timid, and will either bury themselves or roll into a ball if feeling threatened.
Some predators do pose a serious threat to echidnas, including goannas, dogs, foxes, wild cats and snakes.
It was once thought that snoozing echidnas did not enter a state of rapid eye movement (REM) sleep. As it turns out, they do experience REM sleep, but only when the temperature is around 25 °C (77 °F).
Echidnas are also skilled swimmers, and will often enter water to bathe and groom themselves.
This is an albino echidna.
Albino echidnas are noted for their pink eyes and white spines.
What is an echidna? They’re like a cross between an ant-eater and a hedgehog, with their long snout noses and quills. However, echidnas are not closely related to either animal and pretty much stand alone as one of two egg-laying mammals on Earth (the other being the platypus). So what exactly makes the echidna so unique? Simply scroll through the gallery above to discover some amazing facts about this strange and wonderful creature.